Background: Use of large caliber [≥18 mm body diameter (BD)] self-expanding metal stents (SEMS) for management of malignant dysphasia is associated with substantial adverse event (AE) and mortality rates (MRs). We sought to determine dysphagia response, stent migration rates, and AE and MRs, for small caliber covered SEMS (sccSEMS) with BDs between 10-16 mm in malignant dysphagia. Results: DS improved in 30 of 31 patients (97%). The median DS decreased from 3 to 2 (P<0.0001). The median effective duration of first sccSEMS placement was 116 (95% CI: days. Major and minor AE rates were 6.5% and 19.4% respectively. No stent related deaths were encountered. The overall migration rate was 36% (18/50). The anticipated migration rate was 45.7% (16/35) and the unanticipated migration rate was 13.3% (2/15) (P=0.052). Positive effective clinical outcome occurred in 93.5% (29/31) of cases.
Conclusions:In malignant dysphagia, direct endoscopic sccSEMS placement provided acceptable dysphagia control and migration rates with substantial reductions in stent related AEs and MRs compared to those reported for large caliber SEMS. The median dysphagia score (DS) improved to 1 in both groups of patients. However, the rigid stent group experienced 14% procedure related mortality, whereas, the SEMS group experienced no procedure related mortality. Similar complication and MRs were observed by others (5-7). Uncovered SEMS rapidly replaced rigid stents for management of malignant dysphagia (8). However, frequent tumor in-growth obstruction problems were encountered (7,(9)(10)(11). Covering the stent mesh reduced tumor in-growth, but increased SEMS migration rates (12)(13)(14). To address both the tumor in-growth problem and the migration problem, manufacturers pursued various design modifications to include covering only a portion of the SEMS body, increasing the SEMS BD, changing the shape of the SEMS body, or a combination of all three.A randomized controlled trial by Siersema et al. (15) of partially covered and covered SEMS designs from three different manufacturers suggested that SEMS with BDs >20 mm were less likely to migrate when placed across distal esophagus and cardia malignant strictures. However, major stent related complications (perforation, bleeding, fever, pressure necrosis, severe pain) occurred in 18% to 36% of patients and overall 30-day mortality was 15%. In the multicenter randomized Dutch SIREC trial (16), 18 and 23 mm BD partially covered SEMS were compared to brachytherapy as palliation for inoperable esophageal adenocarcinoma. SEMS migration occurred in 17% and tumor in-or over-growth occurred in 15% of patients randomized to treatment with the partially covered SEMS. Major stent related complications occurred in 25% of patients. Stent related mortality was 9%.The available data from existing studies suggests that the major complication and MRs for covered or partially covered SEMS with BDs ≥18 mm are similar to those produced by the non-expandable rigid legacy stents that SEMS were designed to replace. Upon...